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Polyamide
A polyamide is a polymer with repeating units linked by amide bonds. Polyamides occur both naturally and artificially. Examples of naturally occurring polyamides are proteins, such as wool and silk. Artificially made polyamides can be made through step-growth polymerization or solid-phase synthesis yielding materials such as nylons, aramids, and sodium polyaspartate. Synthetic polyamides are commonly used in textiles, automotive industry, carpets, kitchen utensils and sportswear due to their high durability and strength. The transportation manufacturing industry is the major consumer, accounting for 35% of polyamide (PA) consumption. Classification Polymers of Amino acid, amino acids are known as polypeptides or proteins. According to the composition of their main chain, synthetic polyamides are classified as follows: All polyamides are made by the formation of an amide function to link two molecules of monomer together. The monomers can be amides themselves (usually in the for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer
A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon 6-6
Nylon 66 (loosely written nylon 6-6, nylon 6/6, nylon 6,6, or nylon 6:6) is a type of polyamide or nylon. It, and nylon 6, are the two most common for textile and plastic industries. Nylon 66 is made of two monomers each containing 6 carbon atoms, hexamethylenediamine and adipic acid, which give nylon 66 its name. Aside from its superior physical characteristics, nylon 66 is attractive because its precursors are inexpensive. Synthesis and manufacturing Hexamethylenediamine (top) and adipic acid (bottom), monomers used for polycondensation of Nylon 66. Nylon 66 is synthesized by polycondensation of hexamethylenediamine and adipic acid. Equivalent amounts of hexamethylenediamine and adipic acid are combined in water. In the original implementation, the resulting ammonium/carboxylate salt was isolated and then heated either in batches or continuously to induce polycondensation.n(HOOC - (CH2)4 - COOH) + n(H2N - (CH2)6 - NH2) -> OC - (CH2)4 - CO - NH - (CH2)6 - NH - n + (2n - 1) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teijin
is a Japanese chemical industry, chemical, pharmaceutical industry, pharmaceutical and information technology company. Its main fields of operation are high-performance fibers such as aramid, carbon fibers & composites, healthcare, films, resin & plastic processing, polyester fibers, products converting and information technologies, IT products. The company is listed on the first section of the Tokyo Stock Exchange and is a constituent of the Nikkei 225 stock index. As of March 2014, the Teijin Group comprises 151 companies, 56 in Japan and 95 overseas. Teijin is a member of the Mitsubishi UFJ Financial Group (MUFJ) keiretsu. Business segments and products * Advanced Fibers & Composites Business ** Aramid fibers ** High-performance polyethylene ** High-performance polyester fibers ** Polyethylene naphthalate, PEN fibers ** Artificial leather ** Carbon-fiber-reinforced polymer, Carbon fiber reinforced composites ** Flame retardant, Flame-resistant fibers * Electric Materials & Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nomex
Nomex is a flame-resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967. Properties Nomex and related aramid polymers are related to nylon, but have aromatic backbones, and hence are more rigid and more durable. Nomex is an example of a ''meta'' variant of the aramids (Kevlar is a ''para'' aramid). Unlike Kevlar, Nomex strands cannot align during filament polymerization and have less strength: its ultimate tensile strength is 340 MPa. However, it has excellent thermal, chemical, and radiation resistance for a polymer material. It can withstand temperatures of up to 370 °C. Production Nomex is produced by condensation reaction from the monomers ''m''-phenylenediamine and isophthaloyl chloride. It is sold in both fiber and sheet forms and is used as a fabric where resistance from heat and flame is required. Nomex sheet is actually a calendered paper and made in a similar fashion. Nomex Type 410 paper was the first Nomex paper dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kevlar
Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s as a replacement for steel in racing tires. It is typically spun into ropes or fabric sheets that can be used as such, or as an ingredient in composite material components. Kevlar has many applications, ranging from bicycle tires and racing sails to bulletproof vests, all due to its high tensile strength-to-weight ratio; by this measure it is five times stronger than steel. It is also used to make modern marching drumheads that withstand high impact; and for mooring lines and other underwater applications. A similar fiber called Twaron with the same chemical structure was developed by Akzo in the 1970s; commercial production started in 1986, and Twaron is now manufactured by Teijin. History Poly-paraphenylene terephthalamide (K2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphenylenediamine
''p''-Phenylenediamine (PPD) is an organic compound with the formula C6H4(NH2)2. This derivative of aniline is a white solid, but samples can darken due to air oxidation. It is mainly used as a component of engineering polymers and composites like kevlar. It is also an ingredient in hair dyes and is occasionally used as a substitute for henna. Production PPD is produced via three routes. Most commonly, 4-nitrochlorobenzene is treated with ammonia and the resulting 4-nitroaniline is then hydrogenated: :ClC6H4NO2 + 2 NH3 → H2NC6H4NO2 + NH4Cl :H2NC6H4NO2 + 3 H2 → H2NC6H4NH2 + 2 H2O In the DuPont route, aniline is converted to diphenyltriazine, which is then converted by acid-catalysis to 4-aminoazobenzene. Hydrogenation of the latter affords PPD.Robert A. Smiley "Phenylene- and Toluenediamines" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2002, Wiley-VCH, Weinheim. Uses Precursor to polymers PPD is a precursor to aramid plastics and fibers such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evonik
Evonik Industries AG is a stock-listed German specialty chemicals company headquartered in Essen, North Rhine-Westphalia, Germany. It is the second largest chemicals company in Germany, and one of the largest specialty chemicals companies in the world. It is predominantly owned by the RAG Foundation and was founded on 12 September 2007 as a result of restructuring of the mining and technology group RAG. Evonik Industries united the business areas of chemicals, energy and real estate of RAG, while mining operations continue to be carried out by RAG. Since then, the energy and real estate business areas have been divested, with no share being held in the former and a minority share still being held in the latter. Its specialty chemicals business generates around 80% of sales in areas in which it holds leading market positions. Evonik Industries employs about 37,000 people and carries out activities in more than 100 countries. The operating activities are organized into six ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terephthalic Acid
Terephthalic acid is an organic compound with formula C6H4(CO2H)2. This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several million tonnes are produced annually. The common name is derived from the turpentine-producing tree ''Pistacia terebinthus'' and phthalic acid. History Terephthalic acid was first isolated (from turpentine) by the French chemist Amédée Cailliot (1805–1884) in 1846. Terephthalic acid became industrially important after World War II. Terephthalic acid was produced by oxidation of ''p''-xylene with dilute nitric acid. Air oxidation of ''p''-xylene gives ''p''-toluic acid, which resists further air-oxidation. Conversion of ''p''-toluic acid to methyl p-toluate (CH3C6H4CO2CH3) opens the way for further oxidation to monomethyl terephthalate, which is further esterified to dimethyl terephthalate. In 1955, Mid-Century Corporation and ICI announced the bromide-promoted oxida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexamethylenediamine
Hexamethylenediamine is the organic compound with the formula H2N(CH2)6NH2. The molecule is a diamine, consisting of a hexamethylene hydrocarbon chain terminated with amine functional groups. The colorless solid (yellowish for some commercial samples) has a strong amine odor. About 1 billion kilograms are produced annually.Robert A. Smiley "Hexamethylenediamine" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. Synthesis Hexamethylenediamine was first reported by Theodor Curtius. It is produced by the hydrogenation of adiponitrile: :NC(CH2)4CN + 4 H2 → H2N(CH2)6NH2 The hydrogenation is conducted on molten adiponitrile diluted with ammonia, typical catalysts being based on cobalt and iron. The yield is good, but commercially significant side products are generated by virtue of reactivity of partially hydrogenated intermediates. These other products include 1,2-diaminocyclohexane, hexamethyleneimine, and the triamine bis(hexamethylenetriam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphthalamide
Polyphthalamide (aka. PPA, High Performance Polyamide) is a subset of thermoplastic synthetic resins in the polyamide (nylon) family defined as when 55% or more moles of the carboxylic acid portion of the repeating unit in the polymer chain is composed of a combination of Terephthalic acid, terephthalic (TPA) and Isophthalic acid, isophthalic (IPA) acids. The substitution of aliphatic diacids by aromatic diacids in the polymer backbone increases the melting point, glass transition temperature, chemical resistance and stiffness. PPA based resins are molded into parts to replace metals in applications requiring high temperature resistance such as automotive powertrain components, the housing for high temperature electrical connectors and many other uses. Structure The diamines in PPAs are Aliphatic compound, aliphatic. PA6T homopolymer melts at 371 °C, which renders it intractable. To make usable polymers, it is necessary to lower the melting point, which can be achieve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radici Group
RadiciGroup is an Italian corporation with a network of production and sales sites located in Europe, North America, South America and Asia. RadiciGroup is one of the world’s leading producers of a wide range of chemical intermediates, polyamide polymers, engineering plastics, synthetic fibres and nonwovens. The headquarters of the Group remain in Bergamo (Italy), specifically in Gandino, where back in 1941 the founder Pietro Radici established the first textile company. Across generations the solid family tradition has into the secret of the Group’s international success. Since 2018, the company has been one of the main sponsors of Bergamo-based football club Atalanta. Production chain RadiciGroup manages diversified businesses worldwide focused on chemicals, plastics and synthetic fibres with total control over its production chain, from products such as adipic acid, polyamide 6 and polyamide 6.6 to yarns and engineering plastics. This control constitutes one of RadiciGrou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arkema
Arkema S.A. is a publicly listed, multi-national manufacturer of specialty materials, headquartered in Colombes, near Paris, France. It has three specialty materials segments (or divisions); adhesives, advanced materials and coatings. A further segment covers chemical intermediates. The company was created in 2004, as part of French oil major Total's restructuring of its chemicals business, and floated on the Paris stock exchange in May 2006. Turnover in 2021 was €9.5 billion. Arkema operates in more than 55 countries and has 20,200 employees, 13 research centers and 144 production plants. History Arkema itself was created when French oil major Total restructured its chemicals business in 2004, but the company's roots go back many years. Origin and evolution In 1971, Elf and Total merged their chemical operations into Aquitaine Total Organico (ATO), a joint subsidiary. The same year saw the creation of Produits Chimiques Ugine Kuhlmann (PCUK). The joint venture was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
